reactjs - How to call method with bind(this) inside a websocket event -


i using react , websocket test communication:

class class extends react.component {    constructor(props) {     super(props);     this.state = {...};     this.generatemsg= this.generatemsg.bind(this);     this.sendmsg = this.sendmsg.bind(this);   }    //generate random array   generatemsg(n) {return [...]}    //websocket sendmsg   sendmsg(){     const wsclient = new websocket(url);     wsclient.onopen = function(){       wsclient.send(this.generatemsg(40));     }   }    render() {     return (       <button onclick={this.sendmsg}>{this.state.namelist}</button>     );   } }  reactdom.render(...);

always raises err "this.generatemsg not function", how call method bind(this) inside websocket event please?

use arrow function this:

    wsclient.onopen = () => {       wsclient.send(this.generatemsg(40));     }

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